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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi all,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I have a general question regarding best practice or perhaps better put as right architecture design.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>We are using Drools (Expert in particularly) to model and execute the behavior aspects of our service, which revolves around meeting scheduling between various users.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>My main challenge is how to properly structure the rules so that they provide the desired flexibility to both modify and control over time.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Following is a small example which illustrates my question:<o:p></o:p></p><p class=MsoNormal>I need to determine a specific execution time and it is based on many conditions and in general about 15 scenarios where I create a rule per scenario. I find that there is a wide set of conditions that are common to all scenarios.<o:p></o:p></p><p class=MsoNormal>So for example a rule would look like: <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>when <o:p></o:p></p><p class=MsoNormal>a1 == X1<o:p></o:p></p><p class=MsoNormal>a2 == X2<o:p></o:p></p><p class=MsoNormal>a3 == X3<o:p></o:p></p><p class=MsoNormal>a4 == X4<o:p></o:p></p><p class=MsoNormal>b1 == Y1<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Then <o:p></o:p></p><p class=MsoNormal>Something …<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Another rule would be <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>when <o:p></o:p></p><p class=MsoNormal>a1 == X1<o:p></o:p></p><p class=MsoNormal>a2 == X2<o:p></o:p></p><p class=MsoNormal>a3 == X3<o:p></o:p></p><p class=MsoNormal>a4 == X4<o:p></o:p></p><p class=MsoNormal>b2 == Y2<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Then <o:p></o:p></p><p class=MsoNormal>Something else …<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>As you can see I am duplicating the a’ conditions which are the common conditions and the b’ is a new unique condition. It seems to me like a poorer code maintainability and possibly performance reduction (but I may be wrong, perhaps this is how rules should be written).<o:p></o:p></p><p class=MsoNormal>I assume this is a common case in rules so my question is what would be the best way (architecturally wise) to implement such cases (e.g. insert a new class that indicates that conditions a’ are set and base the rules on the existence of such a class)<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks <o:p></o:p></p><p class=MsoNormal>Hezi <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>